This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The study titled "Multimodal Evaluation of Networks Underlying Photosensitive Epilepsy in Baboons" is being submitted as a NIH Exploratory/Developmental Research Grant Program (R21 Parent) for review (PA-06-181). The mechanisms underlying generalized epilepsy in humans are still unknown. The objective of this study is to correlate regional blood flow changes identified by functional neuroimaging with spontaneous epileptic discharges and photoepileptic responses recorded by intracranially implanted electrodes, with the eventual goal of identifying in networks underlying the photosensitive generalized epilepsy of the baboon. We will also utilize transcranial magnetic stimulation in addition to intermittent light stimulation to evaluate the respective contribution of motor and visual cortex activations to the epileptic networks. This study will generate preliminary data for the analysis of visual and motor connectivity in photosensitive and healthy baboons using structural equation modeling. It will also determine candidate regions responsible for the generation of spontaneous epileptic discharges and photoepileptic responses for subdural grid or microelectrode array implantation. With a multimodal approach, we aim to develop a model for photosensitive generalized epilepsy which can be implemented for the evaluation of the biological effects of new antiepileptic medications or neurosurgical interventions.